JavaScript closest

When it comes to finding relationships between elements, we traditionally think of a top-down approach. We can thank CSS and querySelector/querySelectorAll for that relationship in selectors. What if we want to find an element's parent based on selector?

To look up the element tree and find a parent by selector, you can use HTMLElement's closest method:

// Our sample element is an "a" tag that matches ul > li > a
const link = document.querySelector('li a');
const list = a.closest('ul');

closest looks up the ancestor chain to find a matching parent element -- the opposite of traditional CSS selectors. You can provide closest a simple or complex selector to look upward for!